Low-e housewrap

ABSTRACT

A low-E housewrap having improved energy efficiency protection against air infiltration and moisture build-up in buildings. The aforementioned low-E housewrap material utilizing existing framing openings or without increasing the wall profile of a building. The present invention provides a low-E housewrap material which may be implemented on traditional 2×4 framing having R-15 mass insulation material within existing or newly constructed framing cavities. The material of the present invention also meets requirements for serving as a water resistive barrier as defined by ICC AC38.

The present application claims priority to provisional patentapplication entitled, “LOW-E HOUSEWRAP,” filed on May 21, 2010, andassigned U.S. Application Ser. No. 61/346,916.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to building structure materials,and more specifically to an infiltration barrier used in buildingconstruction to improve energy efficiency and to protect against airinfiltration and moisture build-up in buildings.

2. Description of Related Art

In order to improve the energy efficiency of new and existing buildings,it has been common practice in building new structures, and in residingold structures, to cover the exterior wall sheathing with aninfiltration barrier, for example, prior to installation of a coveringmaterial such as siding. One such infiltration barrier is a high densitypolyethylene fiber sheeting. While infiltration barriers cut down ondrafts and thereby convective heat loss, they provide little othercontribution to the energy efficiency of the structure.

In addition to addressing energy efficiencies of new and existingbuildings, moisture concerns can be one of the worst enemies of home orbuilding construction. Water or moisture or humid air infiltration ifallowed to penetrate behind siding or brick can saturate the wood of abuilding structure, thereby creating an environment that encouragesmildew or rot. A weather resistant barrier has for many years beenapplied to the wood studs of buildings and homes in order to resist themoisture or water generated by weather. Such material is typicallyflexible and in a film or sheet form. Typically, this weather resistantbarrier or “house wrap” is applied to the wooden stud frame before theapplication of a final siding or veneer (e.g. brick, metal, paintedwood). Many such “wrap” products are commercially available such as, forexample: Dupont Tyvek®, Typar®. Housewrap (www.typarhousewrap.com), andBarricade®. building wrap (www.ludlowcp.com).

In 2010 the International Energy Conservation Code (IECC) andInternational Residential Code (IRC) increased the thermal performancerequirements for residential walls. Both of these standards seek toimprove thermal performance and reduce energy needs per dwelling. As ofJanuary 2010 the U-value requirement for geographical area or zones 5-8is 0.057; the reciprocal R-value for wall systems is R-20. The U-factoris the inverse, or reciprocal, of the total R-Value, i.e.:U-factor=1/Total R-Value. The R-Value is the thermal resistance to heatflow. A larger R-Value means that the material has greater thermalresistance and more insulating ability as compared to a smaller R-Value.Such R-Values can be added together. For instance, for homogeneousassemblies, the total R-Value of an insulation assembly is the sum ofthe R-Value of each layer of insulation. These layers may includesheathing and finishes, the insulation itself, air films andweatherproofing elements.

In order to meet the new building requirements, builders have employedadditional building techniques such as altering construction of framedopenings. For example, typically, builders have constructed walls on 2×4framing. However, due to the revised requirements, builders are alteringbuilding designs by constructing walls on 2×6 framing and inserting, forexample, R-20 mass insulation within the respective wall cavity in orderto meet the energy/code regulations mandated within the buildingindustry. These techniques, however, increase construction costs becauseof the added and more expensive construction materials. In addition, theincreased size of framing also produces a loss in living space.Nevertheless, many builders have simply accepted the added cost and lossof living space created by the newly implemented thermal code changes.

Accordingly, a need exists for providing a protective wrap that improvesenergy efficiency and protection against air infiltration and moisturebuild-up in buildings while satisfying newly implemented industry-wideenergy/code regulations. There is also a need for employing a protectivewrap which meets or exceeds the newly implemented code requirements onexisting framing structures or openings and/or without increasing thewall profile of a building.

SUMMARY OF THE INVENTION

The present invention provides a low-E housewrap material which may beimplemented on traditional 2×4 framing having R-15 mass insulationmaterial within existing or newly constructed framing cavities. Thematerial of the present invention also meets requirements for serving asa water resistive barrier as defined by The International Code Council's(ICC) codes and standards used to construct residential and commercialbuildings, including homes and schools (e.g., ICC AC38). Thus, by notincreasing the wall profile in the attempt to meet new industrystandards, the builder does not have to perform additional techniques orprovide additional expenses for constructing framed openings.

Still other aspects, features and advantages of the present inventionare readily apparent from the following detailed description, simply byillustrating a number of exemplary embodiments and implementations,including the best mode contemplated for carrying out the presentinvention. The present invention also is capable of other and differentembodiments, and its several details can be modified in variousrespects, all without departing from the spirit and scope of the presentinvention. Accordingly, the drawings and descriptions are to be regardedas illustrative in nature, and not as restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be understood more fully from the detaileddescription given below and from the accompanying drawings of variousembodiments of the invention, which, however, should not be taken tolimit the invention to the specific embodiments, but are for explanationand understanding only.

FIG. 1 provides a top view of a low-E housewrap material according to anexemplary disclosed embodiment;

FIG. 2 provides a cross-sectional view of a low-E housewrap materialaccording to an exemplary disclosed embodiment;

FIG. 3 provides a cut-away perspective view of a low-E housewrapmaterial according to an exemplary disclosed embodiment;

FIG. 4 provides a top view of a low-E housewrap materials during anassembly method according to an exemplary disclosed embodiment;

FIG. 5 provides a perspective view of the low-E housewrap materialsduring the assembly method of FIG. 4;

FIG. 6 provides a top view of a low-E housewrap materials during acontinued assembly method according to an exemplary disclosedembodiment;

FIG. 7 provides a perspective view of the low-E housewrap materialsduring the assembly method of FIG. 6;

FIG. 8 provides a top view of low-E housewrap materials after assemblyaccording to an exemplary disclosed embodiment;

FIG. 9 provides a bottom view of low-E housewrap materials prior toassembly according to an exemplary disclosed embodiment;

FIG. 10 provides a top view of low-E housewrap materials during anassembly method according to an exemplary disclosed embodiment;

FIG. 11 provides a bottom view of low-E housewrap materials afterassembly according to an exemplary disclosed embodiment;

FIG. 12 provides an exemplary exterior wall according to an exemplarydisclosed embodiment; and

FIG. 13 provides a low-E housewrap material application to the exemplarywall structure of FIG. 12. according to an exemplary disclosedembodiment.

DETAILED DESCRIPTION

A low-E housewrap is described. In the following description, forpurposes of explanation, numerous specific details are set forth inorder to provide a thorough understanding of the exemplary embodiments.It is apparent to one skilled in the art, however, that the presentinvention can be practiced without these specific details or with anequivalent arrangement.

Referring now to the drawings, wherein like reference numerals designateidentical or corresponding parts throughout the several views, FIG. 1illustrates a top view of low-E housewrap materials according to onedisclosed embodiment of the present invention. By way of example, twopieces of the low-E housewrap materials 10, 12 are shown. Each of thetwo pieces of low-E housewrap materials 10, 12 may comprise flapportions 14, 16, respectively, at one end thereof. At another end thelow-E housewrap material may include an adhesive strip 18 such as thatprovided on low-E housewrap material 10. In a preferred embodiment, thetop surface 20, 22 of the low-E housewrap materials 10, 12,respectively, is a reflective material such as a layer of reinforcedfoil material.

Turning to FIG. 2, a cross-section of the low-E housewrap material 12 isshown. The low-E housewrap material 12 may comprise an assembly ofproduct component parts including, for example, a reflective foilmaterial 34, foil reinforcement 26, and a foam material 28. In oneembodiment, the reflective material may comprise a facing ofapproximately 99.4% polished aluminum. It is noted that the reflectivematerial may comprise a facing having any suitable amount of aluminum,for example, greater than about 90%, preferably between about 90% andabout 99.9%, even more preferably between about 99.0% and about 99.9%.The reflective foil material 34 may be non reinforced on one side. Onthe other side, the reflective foil material 34 may comprise a foilreinforcement 26 including, for example, a scrim foil reinforcing 30(e.g., see FIG. 3). Scrim is a term known in the art to consist ofcrossed lines of plastics material which serve to strengthen the overallproduct and to prevent stretching damage to the layers. The reflectivefoil material 34 and foil reinforcement 26 may be applied over andbonded to the foam material 28. The scrim foil reinforcing 30 issufficient to provide a tensile strength of approximately 23 pounds perinch width in a machine direction and 25 pounds per inch width in across machine direction on a low-E housewrap material test specimen cutapproximately 1″ wide by 9″ long in standard ambient lab conditions. Thefoam material 28 serves as a polyolefin thermal break such as onecomprising a closed cell polyethylene foam. In a preferred embodiment,the nominal thickness of the polyolefin thermal break is approximately¼″ (0.25″). It is noted that the nominal thickness of the polyolefinthermal break may be any suitable thickness, for example, greater thanabout ⅛″ (0.125″) and less than about ⅜″ (0.375″). Thicknesses aboveabout ¼″ are within the scope of the present invention. It is noted thata thickness greater than about ¼″ may require use of 2×6 framing insteadof the more traditional 2×4 framing. The low-E housewrap 12 may alsoincorporate a self adhered drainage plane 24 feature as furtherdescribed below.

Thus, the invention includes a layer of polyethylene foam which servesas a support for the other added component layers. Polyethylene foam orequivalent polypropylene foam may be utilized, both being in thechemical family designated as polyolefins. A thin layer of aluminum foilis bonded indirectly to one or both sides of said foam layer. Thinpolyethylene layers are placed between the aluminum foil and the foamedlayer. The thin polyethylene is bonded to the aluminum foil layer togreatly improve its resistance to tearing. This strengthening featuremeans that the end product has a much wider use than has been known inthe art. A layer of strengthening scrim may be added to further enhancethe product integrity. In practice of the invention, the various layersadjoin one another after being flame or heat roller laminated together.

In certain embodiments and in practice of the invention, both sides ofthe foam layer may be covered with layers as described above. The endproduct may thus appear identical on either side with the aluminum foillayers being externally located. Thus, use and installation issimplified since the product may be used with either side facing outsince both external faces are identical. The resulting bonded layers areeasily rolled, transported and installed without requiring special toolsor environmental precautions which must be taken with many other priorart insulations.

Turning to FIG. 3, the low-E housewrap 12 comprises perforations 32sufficiently spaced to ensure that the low-E housewrap material does notact as a vapor barrier. In one preferred embodiment, the perforations inthe low-E housewrap are generated from perforation system consisting of1/16″ punchers placed in four holes per 1.25 square inch sequence on acollar mechanism. The collar mechanism is mounted to a drive rollassembly for perforation of the low-E housewrap wherein a 1.25 squareinch perforation pattern is achieved on the finished product. Aperforation pattern of 1.25 square inch allows low-E housewrap 12 tomeet the criteria for perms, water vapor transmission and waterresistance while maintaining an effective emissivity rating. This isunique and contrary to industry standards wherein in many applications,micro perforations are generated in housewraps using needles for vaporpenetration. However, in such convention applications, the microperforations are susceptible to resealing when exposed to highertemperatures. This affect may trap moisture and induce undesirableresults such as mold and rot. In contrast, the present perforationpattern of the prescribed invention eliminates the possibility resealingwhen exposed to higher temperatures. Spaced in approximately 1.25″square perforations, the low-E housewrap material achieves a preferredpermeance and water vapor transmission of approximately 7 perm or 40g/day/m². As such, the present low-E housewrap material performs withinthe optimal permeance and water vapor transmission range of about 5 toabout 20 perm.

The present low-E housewrap material meets the Standard Specificationfor Reflective Insulation, C 1224-03, Section 6, 6.1, which states that“Low emittance materials shall have a surface with an emittance of 0.10or less, in accordance with test Method C 1371.” Specifically, thepresent low-E housewrap material achieves an emittance of 0.10 or less,more specifically within a range of about 0.03 to about 0.05, inaccordance with test Method C 1371.

Accordingly, the product low-E housewrap material of the presentinvention is constructed to include the following approximateperformance characteristics:

Test Description Test Results Perm Test 7 perms ASTM E-96 Water AsReceived 23 hrs Resistance Pass ASTM D-779 Weathered 23 hrs PassUltraviolet light No Cracking Accelerated Aging No Cracking TensileStrength 23 lbs/inch (machine direction) 25 lbs/inch (cross direction)U-value .056 vinyl Wall (zone 5-7) 2010 IECC U-value .051 brick Wall(zone 5-7) 2010 IECC U-value .063 Stone Wall (zone 5-7) 2010 IECC

Although the use of 1/16″ punchers at a rate of four holes per 1.25square inch is described above and represents one of many preferredembodiments of the present invention, other size punchers may be usedand other rates of holes per given area are within the scope of thepresent invention. For example, the diameter of the puncher may bevaried to any suitable size and the rate may be modified to achieve theparticular permeance and emittance standards required by a particularbuilding code, specification or other requirement.

The system U-values described in The Evaluation of Thermal Resistance ofa Building Envelope Assembly demonstrates the performance of wood framedwalls (2×4 construction 16″ on center). The U-value calculations arebased on methods outlined by the ASHRAE Handbook of Fundamentals. TheU-value performance of these systems achieve a U-value between 0.051(brick), 0.056 (vinyl) and 0.063 (stone) satisfying or exceedingrequirements for zones 1-7 established by 2010 IECC Code Table 402.1.3or equivalent UA alternative values established by other code bodies.

Flap portion 16 is illustrated in FIG. 3. This overlapping flange servesas a self adhered drainage plane 24. During assembly of one or morelow-E housewrap sections, the flap portion 16 may be assembled to coveran edge of an abutting portion of another low-E housewrap materialsection in order to seal the edge. For example, turning to FIGS. 4 and5, a first section 10 of low-E housewrap material is positioned near asecond section 12 of low-E housewrap material. The flap portion 16 ofthe second section 12 of low-E housewrap material may be disposed overan edge portion 38 of the first section 10 of low-E housewrap material.In one embodiment, the aforementioned edge portion 38 may include anadhesive strip 18 for retaining the flap portion 16 thereon. Theadhesive strip 18 may be employed on the top surface 20 such as on thereflective foil material 34. While the adhesive strip 18 has beendescribed and shown in the drawings for illustrative purposes, any meansmay be employed which is suitable for retaining the flap portion 14 overthe edge portion 38 in order to provide a water resistive barrierbetween the abutting sections of low-E housewrap materials.

Turning to FIGS. 6 and 7, a protective film is removed to expose theadhesive strip 18 in preparation for securing the flap portion 16 overthe edge portion 38. The flap portion 16 is contacted to the adhesivestrip 18 and secured over the edge portion as illustrated in FIG. 8.This assembly serves to provide a water resistive barrier between twoabutting sections of low-E housewrap materials of the present inventionto effectively seal their respective edges and allow water runoff fromone low-E housewrap material section to another low-E housewrap materialsection.

A bottom view vantage point of abutting low-E housewrap materials isillustrated in FIGS. 9-10. Again, the first section 10 of low-Ehousewrap material is positioned near the second section 12 of low-Ehousewrap material. The flap portion 16 of the second section 12 oflow-E housewrap material is disposed over an edge portion 38 of thefirst section 10 of low-E housewrap material. Edge portion 38 mayinclude an adhesive strip 18 for retaining the flap portion 16 thereon.As a sufficient force is applied, for example, to flap portion 16 tocontact the adhesive strip 18, the flap portion 16 is held in retentionover the edge portion 38 as shown, for example, in FIG. 11. It is clearfrom FIG. 11 that, in a final assembly arrangement, a foam edge portion56 of a first low-E housewrap material 10 abuts a foam edge portion 58of a second low-E housewrap 12. Accordingly, the assembled sectionsserve to provide a water resistive barrier between two abutting sectionsof low-E housewrap materials of the present invention.

In order to improve the energy efficiency of new and existing buildingstructures, application of the herein described low-E housewrap servesto cover the exterior wall sheathing with an infiltration barrier, forexample, prior to installation of a covering material or exterior finishsuch as siding, brick, stone, masonry, stucco and concrete veneers, forexamples. The herein described low-E housewrap also serves to protectagainst air infiltration and damaging moisture build-up. Airinfiltration may occur in typical construction through, among otherplaces, sheathing seams and cracks around windows and doors. Moisturebuild-up can occur externally in the wall cavity from, for example,leaking exterior finishes or coverings, and cracks around windows anddoors. The low-E housewrap of the present invention does not trap thewater, but rather allows it to flow downward so as to exit the wallsystem.

Installation procedures of the presently described low-E housewrapinclude those as described, for example, in the technical manual for ESPLow-E® Housewrap utilized on exterior walls and under a primary barrier.The technical manual for ESP Low-E® Housewrap is submitted herewith andis hereby fully incorporated herein by reference. Turning to FIG. 12, anexemplary exterior wall assembly 40 is constructed and prepared forreceiving the low-E housewrap material of the present invention. In theillustrated example, a window opening 42 is shown. In a preferredembodiment, the low-E housewrap is employed after the walls have beenconstruction and all sheathing and flashing details have been installed.The low-E housewrap material is preferably applied before doors andwindows have been set inside framed openings and prior to theinstallation of the primary wall covering.

Turning to FIG. 13, a first low-E housewrap material is applied to thewall assembly 40. The reflective side of the low-E housewrap material isinstalled facing outwardly. In one preferred embodiment, a roll of low-Ehousewrap material is unrolled horizontally starting at the corner of apreferred exterior wall 40. The flange side or flap portion (e.g., 14,16 of FIG. 1) of the roll is installed facing downwardly. The low-Ehousewrap material is secured to the exterior wall with fasteners 48such as staples or cap nails (or any other suitable fasteners) atpreferably every 8-12″. When applying another horizontal run of low-Ehousewrap material 44, the foam ends of each applied section of rolledlow-E housewrap material abut together such that the flange 52 of theadditionally applied low-E housewrap material 44 is allowed to overlapthe outside edge 50 of the adjacent low-E housewrap material 46. Thisinstallation ensures that any intruding water is encouraged by thedrainage plane (e.g., 24 of FIG. 2) to flow downwardly.

In a preferred embodiment, the flange 52 is installed to overlap theabutting foam edge by approximately 2″. The low-E housewrap material isinstalled to extend over all of the sill plates by a minimum ofapproximately 1″. The vertical and horizontal seam areas are sealed withsuitable low-E foil tape. The low-E housewrap material may be trimmedaround each framed opening with additional appropriate detailing appliedas per window/door manufacturer and/or code standards.

Once installed, an appropriate exterior covering may beapplied/installed over the low-E housewrap. Such covering may include,but not limited to, siding, brick, stone, masonry, stucco and concreteveneers. The utilization of the herein described low-E housewrapprovides, inter alia, a protective wrap that not only improves energyefficiency in accordance with newly implemented industry-wideenergy/code regulations, but enhances drainage of damaging moisturebuild-up while protecting against air infiltration.

Moreover, other implementations of the invention will be apparent tothose skilled in the art from consideration of the specification andpractice of the invention disclosed herein. Various aspects and/orcomponents of the described embodiments may be used singly or in anycombination. It is intended that the specification and examples beconsidered as exemplary only, with a true scope and spirit of theinvention being indicated by the following claims.

1. A flexible insulation comprising: a base insulating material; acovering material positioned over the base insulating material; and aplurality of perforations, wherein each of the perforations comprises anopening through both the base insulating material and the coveringmaterial.
 2. The flexible insulation of claim 1, wherein theperforations are provided in the flexible insulation at a rate of fourholes per 1.25 square inch.
 3. The flexible insulation of claim 1,wherein the perforations are provided in rows, and wherein at least oneperforation in one row of perforations is offset from anotherperforation in another row of perforations.
 4. The flexible insulationof claim 1, wherein the perforations are generated from a perforationsystem consisting of 1/16″ punchers.
 5. The flexible insulation of claim1, wherein the perforations are provided in a repeating pattern.
 6. Theflexible insulation of claim 1, wherein the flexible insulation is alow-E material.
 7. The flexible insulation of claim 1, wherein the baseinsulating material comprises closed cell polyethylene foam.
 8. Theflexible insulation of claim 1, wherein the base insulating materialcomprises polyolefin.
 9. The flexible insulation of claim 1, wherein thebase insulating material has a thickness of approximately 0.25″.
 10. Theflexible insulation of claim 1, wherein the flexible insulating furthercomprises a reinforcing material positioned between the base insulatingmaterial and the covering material.
 11. The flexible insulation of claim10, wherein the reinforcing material comprises a scrim reinforcingmaterial.
 12. The flexible insulation of claim 11, wherein the scrimreinforcing material provides the flexible insulation with a tensilestrength of approximately 23 pounds per inch width in a machinedirection and 25 pounds per inch width in a cross machine direction on atest specimen made of the flexible insulation, wherein the test specimenhas a size of approximately 1″ wide by 9″ long.
 13. The flexibleinsulation of claim 1, wherein the covering material comprises aluminum.14. The flexible insulation of claim 1, wherein the covering material ismade of approximately 99.4% polished aluminum.
 15. The flexibleinsulation of claim 1, wherein the reinforcing material and the coveringmaterial extend beyond an edge of the base insulating material to form aflap.
 16. The flexible insulation of claim 15, wherein the flap is aself adhered drainage plane.
 17. The flexible insulation of claim 1,wherein the flexible insulation further comprises an adhesive material.18. The flexible insulation of claim 17, wherein the flexible insulationfurther comprises a protective film over the covering material with theadhesive material provided therebetween.
 19. The flexible insulation ofclaim 1, wherein the adhesive material is provided in a strip along anedge of the flexible insulation and is provided on a surface of thecovering material.
 20. The flexible insulation of claim 1, furthercomprising a second covering material positioned over a back side of thebase insulating material.
 21. The flexible insulation of claim 1,wherein the flexible insulation achieves a permeance and water vaportransmission of approximately 7 perm or 40 g/day/m².
 22. The flexibleinsulation of claim 1, wherein the flexible insulation achieves anemittance of 0.10 or less in accordance with test Method C
 1371. 23. Theflexible insulation of claim 1, wherein the flexible insulation achievesan emittance of between about 0.03 and about 0.05 in accordance withtest Method C
 1371. 24. The flexible insulation of claim 1, wherein thecovering material is reflective.
 25. A low-E material comprising: a baseinsulating material, wherein the base insulating material comprisesclosed cell polyethylene foam or polyolefin and wherein the baseinsulating material has a thickness of approximately 0.25″; a coveringmaterial comprising aluminum positioned on the base insulating material;and a plurality of perforations, wherein each of the perforationscomprises an opening through both the base insulating material and thecovering material.